Coke oven fuel distribution



May 7, 1940. w. PAVITT COKE OVEN FUEL DISTRIBUTION Filed Nov. 15, 1933 r M n u a a I a m u MM M Z M ATTORNEY Patented May 7, 1940 coke OVEN FUEL DISTRIBUTION William H. Pavitt, Bronxville, N. Y., assignor to Adele Johnson Wilputte, New Rochelle, N. Y.; Louis Wilputte, executor of said Adele Johnson Wilputte, deceased Application November 15, 1933, Serial No. 698,065

6 Claims.

The present invention consists in improved means for regulating the supply of fuel gas to. the different heating wall hues of a coke oven and particularly a coke oven of the type commonly referred tov as an underiired horizontal coke oven. In a coke oven of the type mentioned, the horizontally elongated coking chambers are arranged in a side by side row extending longitudinally from one end to the other of the coke 10 oven battery or structure, and each pair of adjacent. side by side coking chambers are separated by a heating wall which extends, as do the individual oven chambers, from one side' to the other of the battery, and each heating wall is formed with a multiplicity of side by side vertica'l flues extending in one or more rows along the length of the wall. In general, such a coke oven is provided with regenerator chambers for preheating air, or air and lean fuel gas, and located between pillar walls beneath and parallel to and supporting the oven superstructure including the heating walls and coking chambers, and when heated by the combustion of a rich fuel gas which does not require preheating in the regenerator chambers, such fuel gas 'is supplied to the lower end of the different vertical flues by uprising channels formed in the pillar walls from supply piping beneath the'latter.

Sucl ia supply piping ordinarily includes what may be called heating wall supply pipes which are parallel to the heating walls and each of which has separate branch connections to the uprising channels leading to a plurality of- ,vertical heating flues in an adjacent heating wall, and the general object of the present invention is to provide improved meansv for regulating the flow of gas through said connections.

In the operation of such coke ovens, close regulation of the amounts of fuel supplied to the different heating fines is highly desirable to the end that the different portions of the coal being coked which are respectively adjacent and're ceiving neat from the different vertical flues, may be uniformly coked within the same coking period. In general, the gas burned in and the heating effect of each flue should be respectively different from the amount of gas burned in and the heating effect of every other flue in the same wall as a resultof various factors or conditions.

' One such condition is the greater head radiation losses from the oven structure adjacent the two ends of the charge in each coking chamber. An

I other major cause for non-uniformity in the different flue heating eflects'required, is found ind '55 the taper ofv the coking chambers, each of which in an oven of this general type is ordinarily a couple of inches or so wider at the coke side of the battery at which the coke is expelled from the oven, than at the pusher side at which the pusher'ram employed to expel the coke charges fromthe oven chambers enter the latter. With an oven chamber so tapered, the amount of coal ineach unit of length of the oven chamber proof coal to be coked in successive longitudinal sections of the adjacent oven chambers, but also because of the increase in the length of the heat conducting path from the heating wall to the central plane of each adjacent oven chamber from the narrower end of the latter to its wider end. While-those skilled in the art can compute or quite accurately estimate the different heat-.

ing requirements of the different fiues resulting from the oven taper-and from the radiation lossesat the end of the ovens, in practical operation some variations of the actual heating requirements from the theoretical requirements are experienced as a result of various causes.

It has been customary in ovens of the type mentioned, to provide individual flow regulating provisions in the separate connections between the heating wall supply pipes and the different vertical flues served by them, but the forms or types of such provisions heretofore employed have all been open to the objection that they do not permit'of a sufllciently accurate regulation or adjustment of the heating gas distribution, at

least, in a manner sufiiciently easy and inexpensive from the practical standpoint, and the object of the present invention is to provide regulating provisions for the purpose which are not only practically efiective, reliable and desirably simple, butwhich are inexpensive in respect to their initial construction and installation cost, and in respect tot their service and maintenance cost.

My'invention is characterized by the means which I employ for establishing and adjusting a now regulating constriction in a suitably located portion of the length of each branch pipe connection running from a heating wall supply pipe to the corresponding heating flue. In a preferred practical form of the invention, I produce such a construction by means of a tubular part forming a section of the branch pipe connection and having its bore accurately formed and dimensioned, and preferably including'two oppositely tapered conical portions, so that said tubular part is similar to a Venturi tube, and by means of an obturator which is in the form of a cylindrical bar extending axially through but not filling the most constricted portion of the bore of the special tubular part, and which is so mounted that it may be quickly and easily replaced by another obturator of suitabledifierent diameter when the necessity arises for ad' justing the flow capacity of the flow regulatingconstriction to which it pertains.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, and the advantages possessed by it reference shouldv be had to the accompanying drawing and descriptive matter in whichl have illustrated and described preferred embodiments of the invention.

Of the drawing:

Fig. 1 is a partial transverse section of a coke oven battery, the upper portion of the section being taken on a vertical plane passing centrally through a. heating wall of the battery, and the lower portion of the section on a parallel plane passing through the regenerative space at the side of the pillar wall beneath said heating wall; Fig. 2 is a partial section taken, on the line 22 11:15 Fig. 1 and on a much larger scale than Fig.

; and

Fig. 3 is a partial section taken similarly to" Fig. 2 but illustrating a modified construction.

The coke oven structure shown by way of example in Fig. 1 is of the known type in which each heating wall between an adjacent pair of coking chambers 'is formed with a single row of vertical heating flues I, 2, 3 and 4, etc., extending from one side of the battery to the other, and divided into two sets, all of the flues of one set being connected at their upper ends to an upper horizontal channel B and all of the flues of the other set being connected to a second upper horizontal channel, BA, in end to end relation with the channel B. The set of flues I to 14 form part of one heating unit which includes two regenerator chamber 28 and 2| the flues l to I being connected at their lower ends to the regenerator chamber 20, and the flues 8 to l4 being connected at their lower ends to the regenerator chamber 2i. In such an oven, the flues l5, l6, l1, l8 and |9-and regenerator chamber 22 shown in Fig. 1, constitute part of a second heating unit I similar to the one includingthe flues I to 1.4 and pipe 25, which is separate from the heating wallsupply pipe supplying gas to the remaining flues of the said unit, so that it is unnecessary to provide reversing valves between each heating wall supply pipe and the flues to which it is. connected, in order that the flow may be upward through the regenerator- -chambeniof the unit and the flues ,dirctly connected to it when the flow through the other flues and regenerator chamber of the unit is downward. g

The connections between each heating wall supply pipe 25 and each'of the channels 23 which it supplies with gas, in the form shown in Figs. 1

and 2, comprises an upper pipe section 26 and a lower pipe section 21 leading downward from thepipe 25, a horizontal pipe 28 and a vertical pipe 29 connected at its upper end to the channel- 23, and connections between the lower end of the pipe 21 and the adjacent end of the pipe 28 and between the opposite end of the pipe 28 and the lower end of the pipe 29. The last mentioned connection in the form shown comprises a connection member 38 formed with a chamber 3| and having a threaded opening at its top receiving the lower threaded end of the pipe 29, and having an opposing bottom opening receiving a removable plug 32 and having a lateral threaded opening at one side to-receive the corresponding threaded end of the pipe 28 and having a threaded opening at its opposite side to receive a threaded plug 33. The removal of the plugs 32 and 33 permits the removal of furnace dust or other foreign matter which may collect in the chamber 3! and in the plug 33, and permits the interior walls of the pipe sections 28 and 29 'and the chamber 3| to be inspected and cleaned; As shown the threaded end of the pipe 28 inserted in the connection 30 carries a lock nut 34 provided to permit of variation in the extent of projection of the pipe 28 into the connection 30 to be varied as required to accommodate variations in the lateral separation of -the pipes 21 and 29, while at the same time insuring a gas tight joint between the pipe 28 and the connection 38.

The connection between the-pipes 21 and 28 includes a connection part 35 which may be, and is shown as generally similar to but small in size than the connection part 30; Associated with the part 35 are plugs 36 and 31 which may be generally similar to plugs 32 and 33, respectively, except for a hereinafter described-feature of the plug 36 not needed in the plug 32. The plug 31 is in line with the opening in the connection part 35 into which the corresponding end of the pipe 28 is threaded. The top opening in the connection part 35 receives the lower externally threaded end of the tubular 'part 21 which advantageously is connected at its upper ends by a union 38 to the lower end of the pipe 26. A lock nut 39 on the lower threaded end of the part 21 is provided to insure a tight joint while permitting the part 21 to extend toa greater or lesser distance into the connection part 35 as may be necessary to accommodate variations in the vertical spacing of the different-pipe portions.

The tubular part 21 of each branch pipe connection forms the section or portionof the pipe connection providing the flow regulating constriction which is a characteristic of the present invention. As shown, the bore of the part 21 resembles that of a Venturi tube in that it comflow passage is formed by the annular space be- 78 tween the throat wall and the body In. In the preferred construction illustrated, the obturator has a threaded end portion 4| screwed into a threaded socket formed for the purpose in the plug ll. As will be apparent to those skilled in the art, the associated parts 21 and 40 provide a measuring or flow regulating constriction or oriflce which can be formed readily and inexpensively with highly accurate dimensions. Furthermore, the flow capacity of the orifice or constriction can be accurately adjusted in an easy and inexpensive manner by simply replacing one obturator by another obturator differing from the first only in the diameter of its body portion 40.

Withthe arrangement shown in Fig. 2, furnace dust or other foreign matter dropping downward through the passage 23 from the vertical flue above, collects in the chamber at or on the plug 32, and does not tend to clog or to impair the flow regulating accuracy of theconstriction formed by the parts 21 and 40. This advantage is also obtained with the construction shown in Fig. 3 which differs from that shown in Fig. 2 in I that in Fig. 3, the tubular part 21 is connected into the opening of the connection part which in Fig. 2 receives one end of the pipe 28. In Fig. 3, a pipe 28', the tubular part 21 and a connecting union 42 replace the pipe 28 of Fig. 2.

The construction shown in Fig. 3 is thus exactly like that shown in Fig. 2not only in principle but also in respect to the desirable construction characteristics that the constriction or restricted flow regulating orifice is in one of the two transversely extending sections of what may be regarded as an elbow pipe portion, and that the latter is formed with a wall opening in alignment with said orifice and normally closed by a removable closure part which supports an obturator or throttling part extending axially through the orifice. The formation of such an elbow pipe portion in the fuel gas supply connection to each heating flue of an oven of the type shown, is in accordance with ordinary practice and made desirable by practical ,pipe fitting and cleaning considerations. In effect therefore, the use of my novel distribution provisionsrequire no special features of construction or arrangement aside from the formation of the tubular part .21 and its inclusion in one section of the elbow pipe portion, and the formation of the obturator parts and their attachment to closure parts such as the plugs and 33" which need difier from closure parts ordinarily used in such piping only by their is less apt to adhere to the inner wall of the part 21 or to the surface of the obturator 40, with the vertical disposition of those parts shown in Fig. 2, than with their horizontal disposition shown in Fig. 3.

As shown, the heat r g wall supply pipes associated with each heating wall receive gas from a supply main 42 extend g longitudinally of the .battery through a corr ponding branch supply pipe .43 which preferably includes acut-oif valve 44. The pipe 4! is connected through a reversing" type illustrated, the gas pressures in the, lower ends of the vertical heating flues in which combustion is being initiated in any one condition of operation are ordinarily slightly below atmospheric pressure and-may vary somewhat with conditions of use, but in any normal operating condition,- the difference between any of those pressures and thepressure of the atmosphere ordinarily will not exceed that of two tenths of an inch of water, but the gas pressure in the heating wall supply pipes may and preferably should exceed the pressure of the atmosphere by a substantial amount corresponding to a water head of two inches or more. In accordance with the present invention, the constriction formed by each pipe section 21 and the corresponding part 40 is preferably such that almost the entire pressure drop between each pipe 25 and aheating flue connected thereto occurs at the corresponding pressure drops due to flow occurring in the supply main 42 and in the pipe connections between the main and the different constrictions.

In practice, however, it is ordinarily impossible to make the gas supply pressure high enough to avoid some differences betweenthe gas pressure at the inlet ends of the different tubular parts 21, and the diameters of the different obturators 40 employed in a coke oven battery must be varied to compensate for such gas pressure differences. As previously indicated, other causes may also require some compensating variations in the diameters of the obturators. The-needs just mentioned for different obturator diameters must be taken care of in practical operation, as well as those resulting. from the different amounts of coal coked by heat supplied by different heating wall fiues as a result of even taper, and the radiation losses at the side of the battery. As a result of even taper, the heat, requirement of a flue adjacent the wider end of the oven chamber may be nearly twenty per cent in excess'of that of a flue adjacent the narrower end'of the chamber. As a result of heat radiation losses, however, the heat requirement of the end flue at the pusher? side of the battery ordinarily exceeds the heat requirement of every other flue in the wall except the end flue at the "coke side of the bat- ,tery.

A proper appreciation of the practical problems for which the present invention provides a practically effective and desirable solution, and of characteristic advantages of the present invention, may be facilitated bytaking into account certain practical operation. factors and conditions of use of a coke even of the kind illustrated.

In such an oven each individual oven chargemay well be thirteen or fourteen tons of coal and is completely coked in a coking period which may vary between twelve and twenty hours depending on the need for coke and by products. As is welt known to those skilled in the art, the

j carbonization of a pound of coal in an even of the illustrated requires in the neighborhood of a thousand B. t. u.'s. Even with a very rich heating gas, its B. t. u. value is almost invariably less than six hundred B. t. u.'s per-cubic foot, and the volume of the gas burned in each flue in which combustion is must therefore be very large. In this connection, account should be taken of the fact that, except at the ends of the battery, each heating wall must supply an amount of heat equivalent to that required for the coking ofthe coal in one oven chamber, and that combustion is at anyone time in only one of two groups of heating flues of each heating unit.

For use in an oven operating under the conditions just assumed, the throat diameter of each constriction part 21 'may well be only sevensixteenths of an inch in diameter and the diameters of the throttling part All used may vary from a minimumof two-tenths of an inch to maximum of about three-tenths of an inch. Those skilled in the art will understand, of course, that the dimensions just given may be departed from quite widely in practice, and that the controlling dimension in any case is the cross sectional area of the annular passage between the wall of the throat 21' andthe throttling part 40, and that for the operation of a given oven structure with a given coking time, the orifice area required must be greater or less accordingly as the gas pressure in the pipes 25' is relatively small or large. The orifice dimensions stated are, however, of the order which I consider practical and'desirable for a coke oven of the general capacity mentioned above and.

intended for operation with a normal coking period and with the gas pressure in the'pip'es 25 in excess of atmospheric pressure by about two inches of water. In any event, accurate distribution of the heating gas supply in accordance with the present invention requires, and is made possible by the use of accurately formed parts 40 with minute diiferences in their diameter. However, as those skilled in the art will understand, it is a relatively simple and inexpensive matter to provide parts 40 with the diameter required and the operation of replacing obturators initially installed and found to be toolarge or too small by obturators of the proper I size may be effected sively.

In practice, as those skilled in the art will understand, such replacements will be efiected at times when the corresponding reversing valves and 46 are closed, so that the actual replacement operation of any one obturator need involve nothing more than the removal of the corresponding'plug 36 or 33', and the insertion of a similar plug having mounted in it an obturator 40 of the proper diameter. The ease and rapidity with which such replacements may be made is made especially important from the practical standpoint by the large number of replacements which must be efiected in timing up a battery, during its period of operation. For example, in such a'moderate size coke oven battery as one including fifty oven chambers with fifty-one heating walls and only twenty-eight heating flues in each heating wall, there are over fourteen hundred individual heating gas flue supply connections, every one of which may require one or more than one adjustment in the initial operation of the battery to secure proper heat distribution.

After the battery has once been properly tuned expeditiously and inexpenup little or no need for any general replacement of obturator parts should be required in theabsence of some abnormal change in operating conditions, forwith the normal range of variation in oven coking time required, such varla- 5 tion may be effected, insofar as the fuel gas is concerned by varying the pressure at which gas is supplied to the heating wall supply pipes 25. From time to time, however, replacements of some of the obturators by others of different size 0 may benecessary to secure and maintain the desired distribution, and at more or less regular intervals it will ordinarily be necessary to remove the obturators for cleaning and to permit the piping and particularly the walls of the parts 15 21 to be cleaned. Such cleaning operations are easily efiected with the construction illustrated. While in accordance with the provisions of the statutes,- I have illustrated and described the best form of embodiment of my invention now 50 'known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without depart-' ing from the spirit of my invention as set forth in the appended claims, and that'in some cases 26 certain features of my invention may be used to advantage without a corresponding use of other features.

Having now described my invention, what I claim as new and desire to secure by Letters Pat- 30 cut is:

1. In a coke oven having a multiplicity of heating flues, the combination therewith of a separate heating-gas supply connection to each of. said flues including fiow regulating provisions 35 comprising a restricted orifice and a throttling part replaceably mounted in said connection and extending axially through said orifice.

2. In a cokeoven having a multiplicity of heating flues, the combination therewith of a sepa- 40 rate heating gas supply connection to each of said flues including an elbow pipe portion having a fiow regulating orifice in one of its two transversely extending sections and formed with a wall opening in alignment with said orifice, a replace- 4; able closure part closing said opening and a throttling part supported by said closure part and extending axially through said orifice.-

3. In a coke oven having a multiplicity of heating flues, the combination therewith of a separate go heating gas supply connection to each of said fiues including an elbow pipe portion comprising a vertical section and a horizontal section connected to the lower end of said vertical section and having a flow regulating orifice in said ll 4 verticalsection and formed with a wall opening beneath and in alignment with said orifice, a replaceable closure part closing said opening and a throttling part supported by said closure part and extending axially through said orifice.

4. In an under-fired coke oven of the type comprising a heating wall with a row of vertical combustionfiues therein and a pillar wall beneath 1 and extending longitudinally of said heating wall and serving as a regenerator division wall and formed with vertically disposed fuel gas supply channels each individual to and communicably connected at its upper end with the lower end of an adjacent one of said flues, the improved means for supplying fuel gas in regulated amounts to said channgls comprising fuel gas distribution piping belowsaid pillar wall and including an individual branch for each channel comprising :a verticalsection having an'open upper end come municably connected to thesaid channel and a."

. 2,199,961 horizontal section connected to the lower end of I for flow regulation purposes and formed with a wall opening beneath and in alignment with said portion, a replaceable closure part closing said opening, and a throttling part supported by'said closure part and extending axially through said restricted flow passage portion.

5. In a coke oven having a multiplicity of heating flues, the combination therewith of means for supplying fuel gas to said flues comprising a separate heating gas connection to each of said lines including a member having a passage portion of circular cross section, a second member including an obturator portion of circular cross section, and means for detachably connecting said members with said obturator portion coaxial with and extending into'sald passage portion to thereby provide a restricted annular heating gas flow channel having its outer wall surface formed by the inner surface 01' said passage portion and its inner wall surface formed by the outer surface of said obturator portion, whereby bers by another member diilering from the member replaced only in the diameter or its portion of circularcross section.

6. In a coke oven having a multiplicity 01' heating lines, the combination therewith of a separate fuel gas supply connection to each of said flues comprising a casing part formed with aligned openings and with a third opening intermediate and at right angles to the first mentioned openings, a conduitpart connected to said casing part with its bore in communication with said third opening and forming one section of the fuel gas supply channel, leading to the corresponding flue, a conduit member entering said casing through one of said members having a tubular portion and the other of said members including an obturator portion coaxial with and extending into said tubular portion and thereby forming a second section, annular in cross sec- 1 tion, of said supply channel, whereby the cross sectional area of said second channel section may be varied by replacing one of said members by another member difl'er'ing-thereirom only in the cross section of the said portion thereof.

WIILIAM H. PAVI'I'I. 

